Two-Dimensional Transition Metal Dichalcogenides under Electron Irradiation: Defect Production and Doping
Two-Dimensional Transition Metal Dichalcogenides under Electron Irradiation: Defect Production and Doping
复制标题
DOI：
10.1103/physrevlett.109.035503
复制
发表时间：
2012-07-17
影响因子：
8.6
通讯作者：
Krasheninnikov, Arkady V.
中科院分区：
文献类型：
--
作者：
Komsa, Hannu-Pekka;Kotakoski, Jani;Krasheninnikov, Arkady V.
利用第一性原理原子模拟方法，研究了过渡金属二卤化物(TMDs)原子薄层对电子辐照的响应。我们计算了21个不同化合物中原子的位移阈值能量，并估计了产生缺陷所需的相应电子能量。对于具有代表性的MoS_2结构，我们进行了高分辨率的电子显微镜实验，并通过观察80keV电子束下空位的形成来验证我们的理论预测。我们进一步证明，TMD可以通过用杂质原子填充电子束产生的空位来掺杂。因此，我们的结果不仅揭示了降维体系的辐射响应，而且为设计TMDS的电子结构提供了新的途径。
Using first-principles atomistic simulations, we study the response of atomically thin layers of transition metal dichalcogenides (TMDs)-a new class of two-dimensional inorganic materials with unique electronic properties-to electron irradiation. We calculate displacement threshold energies for atoms in 21 different compounds and estimate the corresponding electron energies required to produce defects. For a representative structure of MoS2, we carry out high-resolution transmission electron microscopy experiments and validate our theoretical predictions via observations of vacancy formation under exposure to an 80 keV electron beam. We further show that TMDs can be doped by filling the vacancies created by the electron beam with impurity atoms. Thereby, our results not only shed light on the radiation response of a system with reduced dimensionality, but also suggest new ways for engineering the electronic structure of TMDs.